COAST GUARD PUBLIC SCHOOL PREPARED BY: ASHUTOSH A. AGRAWAL TOPIC: GLOBAL WARMING CLASS: IX A ROLL NO. 09 SUBJECT: SCIENCE SR NO. | TITLE| PAGE NO. | 1. | AKNOWLEDGEMENT| 3. | 2. | GLOBAL WARMING RELATED FAQ’S| 4. | 3. | GREEN HOUSE EFFECT| 5. | 4. | GLOBAL WARMING IMPACTS| 10. | 5. | HOW TO STOP GLOBAL WARMING| 12. | 6. | Teacher’s Remark| 14. | I ASHUTOSH AGRAWAL OF CLASS IX A WOULD LIKE TO THANK MY BIOLOGY TEACHER MRS. DIPTI MISHRA MAM WHO GAVE ME AN OPPORTUNITY TO MAKE THIS PROJECT. SHE GUIDED ME WHENEVER REQUIRED AND MADE THE WHOLE SENERIO CLEAR IN MY MIND.
FURTHERMORE, I WOULD LIKE TO THANK MY PARENTS TO HELP ME IN CREATING THE PROJECT. Global Warming FAQ What is Global Warming? Global Warming is the increase of Earth’s average surface temperature due to effect of greenhouse gases, such as carbon dioxide emissions from burning fossil fuels or from deforestation, which trap heat that would otherwise escape from Earth. This is a type of greenhouse effect. Is global warming, caused by human activity, even remotely plausible? Earth’s climate is mostly influenced by the first 6 miles or so of the atmosphere which contains most of the matter making up the atmosphere.
This is really a very thin layer if you think about it. In the book The End of Nature, author Bill McKibbin tells of walking three miles to from his cabin in the Adirondack’s to buy food. Afterwards, he realized that on this short journey he had traveled a distance equal to that of the layer of the atmosphere where almost all the action of our climate is contained. In fact, if you were to view Earth from space, the principle part of the atmosphere would only be about as thick as the skin on an onion!
Realizing this makes it more plausible to suppose that human beings can change the climate. A look at the amount of greenhouse gases we are spewing into the atmosphere (see below), makes it even more plausible. What are the Greenhouse Gases? The most significant greenhouse gas is actually water vapor, not something produced directly by humankind in significant amounts. However, even slight increases in atmospheric levels of carbon dioxide (CO2) can cause a substantial increase in temperature. Why is this?
There are two reasons: First, although the concentrations of these gases are not nearly as large as that of oxygen and nitrogen (the main constituents of the atmosphere), neither oxygen or nitrogen are greenhouse gases. This is because neither has more than two atoms per molecule (i. e. their molecular forms are O2 and N2, respectively), and so they lack the internal vibrational modes that molecules with more than two atoms have. Both water and CO2, for example, have these “internal vibrational modes”, and these vibrational modes can absorb and reradiate infrared radiation, which causes the greenhouse effect.
Secondly, CO2 tends to remain in the atmosphere for a very long time (time scales in the hundreds of years). Water vapor, on the other hand, can easily condense or evaporate, depending on local conditions. Water vapor levels therefore tend to adjust quickly to the prevailing conditions, such that the energy flows from the Sun and re-radiation from the Earth achieve a balance. CO2 tends to remain fairly constant and therefore behave as a controlling factor, rather than a reacting factor. More CO2 means that the balance occurs at higher temperatures and water vapour levels.
How much have we increased the Atmosphere’s CO2 Concentration? Human beings have increased the CO2 concentration in the atmosphere by about thirty percent, which is an extremely significant increase, even on inter-glacial timescales. It is believed that human beings are responsible for this because the increase is almost perfectly correlated with increases in fossil fuel combustion, and also due other evidence, such as changes in the ratios of different carbon isotopes in atmospheric CO2 that are consistent with “anthropogenic” (human caused) emissions.
The simple fact is, that under “business as usual” conditions, we’ll soon reach carbon dioxide concentrations that haven’t been seen on Earth in the last 50 million years. Combustion of Fossil Fuels, for electricity generation, transportation, and heating, and also the manufacture of cement, all result in the total worldwide emission of about 22 billion tons of carbon dioxide to the atmosphere each year. About a third of this comes from electricity generation, and another third from transportation, and a third from all other sources. This enormous input of CO2 is causing the atmospheric levels of CO2 to rise dramatically.
The following graph shows the CO2 levels over the past 160 thousand years (the upper curve, with units indicated on the right hand side of the graph). The current level, and projected increase over the next hundred years if we do not curb emissions, are also shown (the part of the curve which goes way up high, to the right of the current level, is the projected CO2 rise). The projected increase in CO2 is very startling and disturbing. Changes in the Earth’s average surface temperature are also shown (the lower curve, with units on the left). Note that it parallels the CO2 level curve very well.
Is the Temperature Really Changing? Yes! As everyone has heard from the media, recent years have consistently been the warmest in hundreds and possibly thousands of years. But that might be a temporary fluctuation, right? To see that it probably isn’t, the next graph shows the average temperature in the Northern Hemisphere as determined from many sources, carefully combined, such as tree rings, corals, human records, etc. These graphs show a very discernable warming trend, starting in about 1900. It might seem a bit surprising that warming started as early as 1900.
How is this possible? The reason is that the increase in carbon dioxide actually began in 1800, following the deforestation of much of Northeastern American and other forested parts of the world. The sharp upswing in emissions during the industrial revolution further added to this, leading to a significantly increased carbon dioxide level even by 1900. Thus, we see that Global Warming is not something far off in the future – in fact it predates almost every living human being today. How do we know if the temperature increase is caused by anthropogenic emissions?
Computer models strongly suggest that this is the case. The following graphs show that 1) If only natural fluctuations are included in the models (such as the slight increase in solar output that occurred in the first half of the 20th century), then the large warming in the 20th century is not reproduced. 2) If only anthropogenic carbon emissions are included, then the large warming is reproduced, but some of the variations, such as the cooling period in the 1950s, is not reproduced (this cooling trend was thought to be caused by sulfur dioxide emissions from dirty power plants). ) When both natural and anthropogenic emissions of all types are included, then the temperature evolution of the 20th century is well reproduced. Is there a connection between the recent drought and climate change? Yes. A recent study by the National Oceanic and Atmospheric Administration gives strong evidence that global warming was a major factor Who studies global warming, and who believes in it? Most of the scientific community, represented especially by the Intergovernmental Panel on Climate Change (IPCC – www. ipcc. h), now believes that the global warming effect is real, and many corporations, even including Ford Motor Company, also acknowledge its likelihood. Global Warming Impacts Many of the following “harbingers” and “fingerprints” are now well under way: 1. Rising Seas— inundation of fresh water marshlands (the everglades), low-lying cities, and islands with seawater. 2. Changes in rainfall patterns — droughts and fires in some areas, flooding in other areas. See the section above on the recent droughts, for example! . Increased likelihood of extreme events— such as flooding, hurricanes, etc. 4. Melting of the ice caps — loss of habitat near the poles. Polar bears are now thought to be greatly endangered by the shortening of their feeding season due to dwindling ice packs. 5. Melting glaciers – significant melting of old glaciers is already observed. 6. Widespread vanishing of animal populations — following widespread habitat loss. 7. Spread of disease — migration of diseases such as malaria to new, now warmer, regions. 8.
Bleaching of Coral Reefs due to warming seas and acidification due to carbonic acid formation — One third of coral reefs now appear to have been severely damaged by warming seas. 9. Loss of Plankton due to warming seas — The enormous (900 mile long) Aleution island ecosystems of orcas (killer whales), sea lions, sea otters, sea urchins, kelp beds, and fish populations, appears to have collapsed due to loss of plankton, leading to loss of sea lions, leading orcas to eat too many sea otters, leading to urchin explosions, leading to loss of kelp beds and their associated fish populations.
Discussing Global Climate Change: Here is a useful list of facts and ideas: 1. Given the strong scientific consensus, the onus should now be on the producers of CO2 emissions to show that there is not a problem, if they still even attempt to make that claim. Its time to acknowledge that we are, at very least, conducting a very dangerous experiment with Earth’s climate. 2. A direct look at the data itself is very convincing and hard to argue with. Ask a skeptical person to look at the data above. The implications are obvious. The best source of data is probably the IPCC reports themselves, which are available at www. pcc. ch (see, for example, the summaries for policy makers). 3. The recent, record-breaking warm years are unprecedented and statistically significant. It is a fact that they are very statistically unlikely to be a fluctuation (and now we can point to specific side effects from those warm temperatures that appear to have induced recent worldwide drought). 4. Lastly, but perhaps most importantly, whether or not you believe in global warming per se, the fact remains that the carbon dioxide levels are rising dramatically — there is no debate about this.
If we continue to use fossil fuels in the way we presently do, then the amount of carbon we will release will soon exceed the amount of carbon in the living biosphere. This is bound to have very serious, very negative effects, some of which, such as lowering the pH of the ocean such that coral cannot grow, are already well known. Ways to Stop Global Warming: Owing to the overall rise in the temperature, the glaciers in the Antarctic region begin to melt which has increased the overall sea level. If this situation continues, many low lying areas will submerge in the near future.
Global warming also increases the occurrences of hurricanes. There are many easy solutions to reduce global warming and its impact. First of all, people should understand the problem and take measures accordingly to save the world. * People should reduce the usage of electrical appliances which emits green house gases. For e. g. the refrigerator releases chloro fluro carbon (CFC) and the incandescent light lamp emits 300 pounds of carbon dioxide a year. This can be replaced by a compact fluorescent light bulb which saves much energy. Follow RRR-Reduce, Reuse, Recycle. People should not dump waste products in the ground. Plant products, food waste, vegetable dump undergoes anaerobic decomposition i. e. they break down to produce methane, a green house gas instead of oxygen. Hence the product usage and wastage should be reduced or recycled for a healthy atmosphere. * Trees absorb a large amount of carbon dioxide. Many trees should be planted since they involve in photosynthesis, food preparation with the help of sunlight. During this process, trees absorb carbon dioxide and exhale oxygen.
Also, existing forests should be saved and usage of plant byproducts shouldn’t be wasted. * Usage of green power prevents 300 kg of carbon dioxide to be emitted into the atmosphere. The electricity obtained from the renewable resources like wind and water is called green power. The cost is also low in case of green power. * Insulation of the ceiling of a house and power saving is the important factor to reduce global warming. The electric appliances should be switched off instead to hold it in stand by mode.
This will save more power since stand by mode consumes 40% of the energy. * People should use only energy efficient appliances. Thermostat should be used for air conditioners since it reduces the temperature automatically. * Consumption of organic food should be increased because organic soil absorb large amount of carbon dioxide. Buying local food reduces the consumption of fuel. Cows emits large amount of methane due to their vegetarian diet. Hence meat consumption should be reduced. Also tetra packs should be used instead of tinned food. Periodic maintenance of the vehicles helps in efficient usage of fuel and reduces release of green house gases. Proper inflation of tyres should be done and fuel wastage should be avoided. We should teach our neighborhood and friends about the cause and impacts of global warming and methods to reduce it. Conservation of forests also forms a factor to reduce global warming. Hence, individuals and government should be concerned about the environment and stop the incoming danger due to global warming. THANK YOU